Arcologies and Population

[atpollard]

The 'Long Range Survey at Jump 1' thread was getting too far off topic, so I moved my response here.

Originally posted by TheEngineer:
I though about higher TL civilisations/colonies, which where less environment dependent anyway ....
Any settlement would perhaps more like archologies, too

Perhaps we could work out a rough max pop capacity, based on the UWP stats, trade codes etc....
Lets just think, isn't there something similar given in MT hard Times ???

Building an Arcology to house a population on a world of size 0-4.

Given the following assumptions:
1. TL = 12
2. each person requires 90 square meters (x 3 m tall) of total living space
3. each person requires 40 square meters (x 3 m tall) of total farming space
4. Arcology must provide all life support – air, radiation shielding, normal gravity
5. All building materials are transported 1 parsec to the colony site.

Therefore:
1. Arcology requires 19.5 dTons per person of living space.
a. 19.5 dTons x 0.1 MCr/dTon = 1.95 MCr structure/shell
b. +0.025 MCr/person = 0.025 MCr life support
c. 19.5 dTons x 0.001 MCr/dTon = 0.0195 MCr transport cost
d. Total Living Space cost = about 2 MCr per person

e. Monthly Life Support = 0.0087 MCr per person
f. Monthly Maintenance Cost = 0.0017 MCr per person
g. Total Monthly Living cost = about 0.01 MCr per person


2. Arcology requires 8.5 dTons per person of farming space.
a. 8.5 dTons x 0.1 MCr/dTon = 0.85 MCr structure/shell
b. +0.025 MCr/person = 0.025 MCr life support
c. 8.5 dTons x 0.001 MCr/dTon = 0.0085 MCr transport cost
d. Total Farming Space cost = about 1 MCr per person.

e. Monthly Life Support = 0.0087 MCr per person
f. Monthly Maintenance Cost = 0.0008 MCr per person
g. Total Monthly Farming cost = about 0.001 MCr per person

Conclusion:
An Arcology designed to house (and not feed) a village of 100 people (Pop=2) would be 1950 dTons, have an initial construction cost of 200 MCr and require 1 MCr of per month to supply/maintain.
An Arcology designed to house and feed a village of 100 people (Pop=2) would be 2800 dTons, have an initial construction cost of 300 MCr and require 1.1 MCr of per month to supply/maintain.

An Arcology designed to house (and not feed) a city of 100,000 people (Pop=5) would be 1.95 million dTons, have an initial construction cost of 200,000 MCr and require 1,000 MCr of per month to supply/maintain.
An Arcology designed to house and feed a city of 100,000 people (Pop=5) would be 2.8 million dTons, have an initial construction cost of 300,000 MCr and require 1,100 MCr of per month to supply/maintain.

Living here would be expensive. Assuming financing similar to a Starship, each prospective inhabitant would need a down payment of 100,000 to 150,000 credits (based on whether food is imported or available in site – important in “Hard Times”) and a mortgage of 8,300 to 12,450 Cr per month for 40 years. Life support would cost an additional 10,000 to 11,000 Cr per month (canned food vs fresh food). … and all of these costs would be quadrupled for a family of four!

Admittedly, these are worst case figures based on HG starship construction (note, however that these costs include 28 dTons of interior ‘furnishings’ plus a power plant for the cost of two standard staterooms). It might be possible to reduce these costs by a factor of 10 by searching for more favorable rules, but that will still be expensive for a family of four – 60,000 Credits to move in and 9380 Cr per month living expenses.

Large populations really need a world with an atmosphere.

 

[coliver988]

There's a description of Azun's arcology system in JTAS 15. No mention of price, but it did mention that "such cities can comfortably house population in excess of 1,500,000 persons, including not only living space but also nearly every other facet essential for life to flourish". Of course Azun is an old industrial world so they did not have to ship things in.

I remember an old R. Silverberg novel from the 70's about arcologies. Different social dynamics for certain!

 

[atpollard]

Most of the cost for the arcology above, comes from the assumed need to protect against micrometeorites, hard vacuum and radiation, while maintaining a starship-like life support system (all requirements for a small world without an atmosphere or magnetic field). On a 'friendly' world, the costs might run closer to 1 percent of the calculated costs – say 6000 Credits for a family of 4 to move in and 938 Cr per month living expenses (even a 'gunner' could afford that).

 

[Icosahedron]

I've not been following the 'Jump 1' thread, so excuse me if this isn't relevant, but:

The transportation costa above assume a routine shipment price of 1000Cr/dT. Shipping may cost more than this on a frontier, where cargo space is in short supply. You may even have to charter a ship to get your maintenance parts delivered.

I run with 10% costs for 'friendly' environments.

 

[LordVince]

Here's another thing to consider -- even for a "harsh" environment -- all those costs assume that the TOTALITY of all needed parts & supplies will come from offworld. No allowance is being made for use of local materials.

Why ship a bazillion tons of concrete across 1 parsec, if it can be made locally? Why ship a gazillion tons of water across 1 parsec, if the planet you're building on has water/ice -- or even if the local starsystem has some available ice asteroids?

I realize that Atpollard's numbers are crunched from Ship Building rules, but maybe, carrying through with that analogy, there might be something like the Architechs Discount for common designs. Not only for the structure, itself, but for, say, "Ease of Construction Environment".

If you're building in an area that has abundant local resources to make use of, then you get a big discount. If you're building someplace that's either hard to work in, or has few, if any, local resources, then the discount would be low -- or even non-existant or an INCREASE in the cost.

IMTU, given the SIZE and WEALTH of some Mega-Corporations, I've postulated the existance of "Colony Development" companies -- they have massive, 100K dTon ships, with factories aboard to fashion raw materials into finished construction products, Lighters to tend the ship & surface workzone, and quarters for thousands of workmen & robots.

IMTU, you could hire these kinds of companies, point at a planet, hand over 100MC, and 6 months later you have a small town on the shores of a lake -- complete with all necessary infrastructure! -- ready for your Colonists to move into.

 

[Golan2072]

Originally posted by Lord Vince:
Here's another thing to consider -- even for a "harsh" environment -- all those costs assume that the TOTALITY of all needed parts & supplies will come from offworld. No allowance is being made for use of local materials.

Why ship a bazillion tons of concrete across 1 parsec, if it can be made locally? Why ship a gazillion tons of water across 1 parsec, if the planet you're building on has water/ice -- or even if the local starsystem has some available ice asteroids?

I completely agree with you. Even inhospitable worlds that would be colonized would ususally be slected for having some key resources on them - most importantly, water. If you have water, you could easily make oxygen and fusion-reactor fuel locally, as well as having your own source of water. Combined with hydroponics, you'll soon cover most life-support costs except for a few minor ones (fertilizers for the hydroponics, equipment spare parts and so on).

Many construction and industrial raw materials could be harvvested from alot of worlds, even Luna; this website has some ideas in that direction.

Additionally, living underground rater than in arcologies would probably be cheaper (and safer in terms of protection from radiation and micro-meteorites); and, with fusion, digging one dton of space out of solid rock costs Cr1,000 (HG). If you could find lava-tubes or other kinds of natural caves, just seal off the entrance and add life-support and you have an instant pressurized environment; if the tube or cave is too long for your needs, just seal a section of it.

 

[Pickles]

I remember a protracted discussions on arcologies ... ah, here it is:

Building an Arcology

 

[atpollard]

Originally posted by the Bromgrev:
I remember a protracted discussions on arcologies ... ah, here it is:

Building an Arcology

The design example at the end still costs over 13,000 credits per person per month in mortgage payments. Arcology living is not cheap.

PS. Don't sweat the transportation costs, they are less than 1 percent of the total cost. It is the space rated hull that is expensive.

 

[Space Cadet]

Originally posted by Employee 2-4601:
</font><blockquote>quote:</font><hr />Originally posted by Lord Vince:
Here's another thing to consider -- even for a "harsh" environment -- all those costs assume that the TOTALITY of all needed parts & supplies will come from offworld. No allowance is being made for use of local materials.

Why ship a bazillion tons of concrete across 1 parsec, if it can be made locally? Why ship a gazillion tons of water across 1 parsec, if the planet you're building on has water/ice -- or even if the local starsystem has some available ice asteroids?

I completely agree with you. Even inhospitable worlds that would be colonized would ususally be slected for having some key resources on them - most importantly, water. If you have water, you could easily make oxygen and fusion-reactor fuel locally, as well as having your own source of water. Combined with hydroponics, you'll soon cover most life-support costs except for a few minor ones (fertilizers for the hydroponics, equipment spare parts and so on).

Many construction and industrial raw materials could be harvvested from alot of worlds, even Luna; this website has some ideas in that direction.

Additionally, living underground rater than in arcologies would probably be cheaper (and safer in terms of protection from radiation and micro-meteorites); and, with fusion, digging one dton of space out of solid rock costs Cr1,000 (HG). If you could find lava-tubes or other kinds of natural caves, just seal off the entrance and add life-support and you have an instant pressurized environment; if the tube or cave is too long for your needs, just seal a section of it. </font>[/QUOTE]Its not the cost of materials that make these things expensive, its the construction cost. I'm sure these habitats aren't made of rare or expensive materials.

As for why you want to ship it across a parsec. Think about it, you can't just bring money to an inhospitable planet and use it to hire locals to construct the habitat out of local materials, for one thing your labor supply may be scarce or non existant. If you build it at an established shipyard, you have experts to hire who know what there doing. To transport an Arcology agross an interstellar distance, you need a special kind of starship called a tug. A Tug would have an oversized Jump drive to accomadate a volume much greater than itself, it attaches to the archology to become one starship with it, then it jumps. Upon arrive at its destination, it places the archology and then detaches, and makes another jump to retrieve another one.

 

[Golan2072]

That's why you'd prefer to use the cheapest possible construction methods - and using caves/lava-tubes, or even digging locally, means that the "hull" and other structural parts could be created for cheap and with no transport cost. Then you manufacture the higher-tech parts a few parsecs away and assemble them on site (by robots, preferrably - less life-support overhead until the main LS system comes online).

Also, colonizing a world such as Mars (i.e. with a Trace or Very Thin atmosphere and sizable ice-caps) would be preferrable over colonizing someplace such as Luna (i.e. vaccuum and the only water being the remanants of crashed comets). With a Trace atmospere, the tensile strength needed for "tent" cities would be lower, making them more feasable and probaby cheaper. Aboundant water ice is a raw material for drinking water, oxygen and hydrogen fuel - the basic nessecities of life). And higher gravity would mean less or no gravitational compensators to plant beneath the floor.

 

[Space Cadet]

One can always opt to rotate a colony for gravity. Even if Grav plates are available, it might be economically attractive to rotate a colony instead as that requires no continuous power inputs.

An example of an archology is the Island Three. An Island Three consists of two cylinders attached together by a long non-rotating truss connecting the spin axis of each cylinder. Each cylinder has hemispheric end caps on both ends, a diameter of 4 miles and a length of 20 miles, each cylinder has an internal land area of 500 square miles in each cylinder, this land is divided into three vallies in a trilateral symmetry that alternate with window Solars of equal area to the land areas the alterate with and each solar stand opposite to a vally to let in sunlight that is reflected by a flat panel planar mirror that can open up and close like the petals of a flower so that it can vary the angle of the sunlight as seen from the opposing valley floor. A flat mirror that is twice the length of the valley would start at the closed position as the cylinder's end cap is pointed toward the star, as the mirror unfolded the sun would appear to rise along an arc beginning at an 11 degree angle as seen at the end of the valley furtherst from the Sun. This Sun will climb until it reaches its zenith directly over head as the mirror reaches a 45 degree angle to the cylinder, and as the mirror unfolds further the sun will appear to descend towards the opposite end of the valley until it reaches 30 degrees and then it will stop. The Solars would then polarize into opacity to simulate dusk and the mirrors will be reeled in back towards their original position to get ready for another sunrise. There would be two of such cylinders. The cylinders represent the living space, the agricultural cylinders would be spaced along a wide circle about each cylinder and counter rotated. Each ag cylinder would contain a square mile of agricultural space and there would be a total of 270 such cylinders about each large cylinder, lets say each one of them was 1 mile in length and 1,681 feet in diameter, this means there is a circle about the large cylinder at least 86 miles in circumference and 27.3 miles in diamter, this require a seperation of about at least that amount, probably 30 miles between the two community cylinders as they rotate in opposite directions as the orient towards the sun.

Now how would you measure the hull displacement of an Island Three? Obviously the inhabitants don't use the entire internal volume of each cylinder, above their heads is 4 miles of air and clouds and then the opposite valley Solar that lets in the light for day. There are two ways of measuring the volume of an island three, one way is to find the volume of the cylinder which is equal to that of a cylinder 20 miles long and 4 miles wide and a sphere 4 miles in radius that is cut in half with two halves capping the equator, multiply that by two to account for both cylinders, then you add in the 270 Ag cylinders for each main cylinder for a total of 540 ag cylinders and each cylinder measures 5280 ft by 1681 ft to produce a square mile of growing area each. Anyone care to calculate the cost of this in Traveller terms?

The other way is to exclud must of the internal air of each cylinder by subtracting an imaginary cylinder of air inside each cylinder that is 6 meters les in diameter than the inner surface area of each cylinder, after all all that volume represents nothing but air, with no structural or technological components associated with it. if there was a roof 3 meters above the ground and vacuum above that, it would be effectively the same as having 4 miles of air obove people's heads if the cylinders were entirely closed around all that air. The people breathing that air and the plants regenerating the oxygen would remain about 3 meters above each valley floor and less.

So what do you thing, how would you calculate the volume and hence the cost of an Island Three in Traveller terms?

 

[atpollard]

Originally posted by Space Cadet:
One can always opt to rotate a colony for gravity. Even if Grav plates are available, it might be economically attractive to rotate a colony instead as that requires no continuous power inputs.

[snip]

So what do you thing, how would you calculate the volume and hence the cost of an Island Three in Traveller terms?

The JTAS No. 23 (now available on CD) has rules for constructing rotating orbital habitats.

While superior to building an arcology on an airless rock ball with no protection from the solar winds, this might not count as ‘establishing a colony on the world’ which is where this whole discussion started. Fusion tunneling space at 1000 cr per dTon (planetoid hull rules) and living with the natural gravity would probably be much cheaper and would count as establishing a colony on the world.

FREE TRIVIA: Paolo Soleri (the inventor of the concept and term ‘arcology’ which is basically a vertically oriented city) proposed ‘Asteromo’ (an orbital arcology of 70,000 people) in his 1969 book “Arcology: The City in the Image of Man”. An actual arcology, called Arcosanti has been under construction for decades.